package com.mingserve.common.core.utils;

import org.springframework.aop.framework.AopContext;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.beans.factory.support.BeanDefinitionBuilder;
import org.springframework.beans.factory.support.DefaultListableBeanFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.context.ApplicationEvent;
import org.springframework.stereotype.Component;

/**
 * spring工具类 方便在非spring管理环境中获取bean
 *
 * @author lvwshuai
 */
@Component
public final class SpringUtils implements BeanFactoryPostProcessor, ApplicationContextAware
{
    /**
     * Spring应用上下文环境
     */
    private static ConfigurableListableBeanFactory beanFactory;
    private static ApplicationContext applicationContext;


    @Override
    public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException
    {
        SpringUtils.beanFactory = beanFactory;
    }

    public void setApplicationContext(ApplicationContext applicationContext) {
        SpringUtils.applicationContext = applicationContext;
    }

    /**
     * 获取spring上下文
     */
    public static ApplicationContext context() {
        return applicationContext;
    }

    /**
     * 获取对象
     *
     * @param name
     * @return Object 一个以所给名字注册的bean的实例
     * @throws org.springframework.beans.BeansException
     *
     */
    @SuppressWarnings("unchecked")
    public static <T> T getBean(String name) throws BeansException
    {
        return (T) beanFactory.getBean(name);
    }

    /**
     * 获取类型为requiredType的对象
     *
     * @param clz
     * @return
     * @throws org.springframework.beans.BeansException
     *
     */
    public static <T> T getBean(Class<T> clz) throws BeansException
    {
        T result = (T) beanFactory.getBean(clz);
        return result;
    }

    public static String getProperty(String key) {
        return null == applicationContext ? null : applicationContext.getEnvironment().getProperty(key);
    }

    /**
     * 如果BeanFactory包含一个与所给名称匹配的bean定义，则返回true
     *
     * @param name
     * @return boolean
     */
    public static boolean containsBean(String name)
    {
        return beanFactory.containsBean(name);
    }

    /**
     * 判断以给定名字注册的bean定义是一个singleton还是一个prototype。 如果与给定名字相应的bean定义没有被找到，将会抛出一个异常（NoSuchBeanDefinitionException）
     *
     * @param name
     * @return boolean
     * @throws org.springframework.beans.factory.NoSuchBeanDefinitionException
     *
     */
    public static boolean isSingleton(String name) throws NoSuchBeanDefinitionException
    {
        return beanFactory.isSingleton(name);
    }

    /**
     * @param name
     * @return Class 注册对象的类型
     * @throws org.springframework.beans.factory.NoSuchBeanDefinitionException
     *
     */
    public static Class<?> getType(String name) throws NoSuchBeanDefinitionException
    {
        return beanFactory.getType(name);
    }

    /**
     * 如果给定的bean名字在bean定义中有别名，则返回这些别名
     *
     * @param name
     * @return
     * @throws org.springframework.beans.factory.NoSuchBeanDefinitionException
     *
     */
    public static String[] getAliases(String name) throws NoSuchBeanDefinitionException
    {
        return beanFactory.getAliases(name);
    }

    /**
     * 获取aop代理对象
     *
     * @param invoker
     * @return
     */
    @SuppressWarnings("unchecked")
    public static <T> T getAopProxy(T invoker)
    {
        return (T) AopContext.currentProxy();
    }

    /**
     * 手动注册Bean
     *
     * @param requiredType 待注册的BeanClass文件
     * @param <T>          bean类型
     * @return 返回Bean对象
     */
    public static <T> T registerBean(Class<T> requiredType) {
        return registerBean(requiredType, requiredType.getSimpleName());
    }

    /**
     * 动态注入bean
     *
     * @param requiredType 注入类
     * @param beanName     bean名称
     */
    public static <T> T registerBean(Class<T> requiredType, String beanName) {
        //获取BeanFactory
        DefaultListableBeanFactory defaultListableBeanFactory = (DefaultListableBeanFactory) beanFactory;
        //创建bean信息.
        BeanDefinitionBuilder beanDefinitionBuilder = BeanDefinitionBuilder.genericBeanDefinition(requiredType);
        //动态注册bean.
        defaultListableBeanFactory.registerBeanDefinition(beanName, beanDefinitionBuilder.getBeanDefinition());
        //获取动态注册的bean.
        return beanFactory.getBean(requiredType);
    }

    public static void publishEvent(ApplicationEvent event) {
        if (null != applicationContext) {
            applicationContext.publishEvent(event);
        }
    }

    /**
     * 观察者模式，推送自自定义事件
     * 使用方式  SpringUtils.getApplicationContext().publishEvent(customEvent);
     * 接收方式 @EventListener(CustomEvent.class)
     *
     * @param event
     */
    public static void publishEvent(Object event) {
        if (null != applicationContext) {
            applicationContext.publishEvent(event);
        }
    }
}
